Carlos Manuel Rodrigues Machado Autonomic Ubiquitous Computing

3.5 Related Middleware Approaches
Some middleware approaches that are emerging are focused on some of the characteristics
mentioned before. These approaches try to provide an abstract middleware layer that allows a
smooth interaction between underlying hardware and the application software. Some of well-known
middleware protocols in this field are: LonWorks, X10, UPnP, OSGi, Jini and oBIX. Some of these
are oriented to control and automation functions, while others concentrate on data streaming and
media management.
The LonWorks 1 is a networking platform specifically created to address the unique
performance, reliability, installation and maintenance needs of control applications. The platform is
built on a protocol created by Echelon Corporation 2 for networking devices over media such as
twisted pair, powerlines, fiber optics and RF. Essential elements in this middleware system include
LonWorks protocol; the implementation of the protocol (usually packed in one single chip called
Neuron Chip); and the network components. The LonWorks protocol 3 is used in the communication
among LonWorks devices. The design of the protocol follows Open Systems Interconnection (OSI)
model. The protocol provides two sets of communication services: the first one enables application
programs in one device to communicate with other devices over the network, the second one
supports network management services, including addressing reconfiguration and controlling device
application programs. LonWorks is an important solution for control networks which was developed
for decreasing the cost and design complexity of distributed control systems. The protocol itself is
media-independent, allowing LonWorks devices to communicate over any physical transport media.
The X10 4 is an international and open industry standard that also focuses on the control of
the devices. It primarily uses power line wiring for signalling and control, where the signals involve
brief radio frequency bursts representing digital information. A wireless radio based protocol
transport is also defined. The commands and signals are broadcast throughout the medium and
picked by the actuators, i.e., a single message can be used by one or more devices, but the failure
1 LonWorks Middleware documentation available online at: http://www.echelon.com/support/documentation/
2 More information available on-line at: http://www.echelon.com
3 LonWorks protocol is also known as LonTalk protocol and ANSI/EIA 709.1 Control Networking Standard.
4 X10 Theory. Available on-line at: http://www.smarthomeusa.com/info/x10theory/
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